Improving Properties in Rigid Urethane Foams Using Glass Bubbles

J.H. Saunders and K.C. Frisch , "Polyurethanes:Chemistrv and Technology, Part 1, Chemistry." Interscience Publishers, N.Y., N.Y. ( 1962).

C.G. Seefried , Jr. and R.D. Whitman , Journal of Cellular Plastics. Sepgember/October, 256-267 (1972).

C.J. Bennning , "Plastic Foams: Volume 1, Chemistry and Physics of Foam Formation," Interscience Publishers, N.Y., N.Y., ( 1969) p. 221.

S.L. DeGisi and T.S. Neet , Journal of Applied Polymer Science, 20, 2021-2029 (1976).